Fire extinguishing liquid



Patented Jan. 11, 1938 UNITED STATES PATENT OFFICE No Drawing.Application June'll, 1936, Serial No. 85,696

7 Claims.

This invention relates to improvements in fire extinguishing liquids,and more particularly to such liquids for use in mechanical fireextinguishers and sprinkler systems.

One of the main features of the invention resides in a fireextinguishing liquid which is highly eflicient in its action forextinguishing fires, and which is less toxic than the liquids generallyused in fire extinguishing apparatus.

Another feature of the invention is to provide a chemical fireextinguishing liquid which is highly volatileso as to rapidly .vaporizewhen subjected to the heat of a fire, which vaporization consumes theheat of the burning material, thus 15 lowering the temperature thereof,and at the same time, the vapor displaces the air and stops combustion.

A further feature of the invention is the provision of a chemical fireextinguishing liquid 20 which is non-damageable to material contactedthereby; which is less harmful than other fire extinguishing chemicals,and which is non-corrosive so as not to affect theworking parts ofvarious apparatus used for dispensing the liquid 25 in fighting fires.

Other features of the invention will be apparent as the followingspecification is proceeded with, and as pointed out in the annexedclaims.

My improved fire extinguishing liquid consists 30 of the followinglisted ingredients and substantially of the proportions set forth:

Per cent Tetrachlorethylene Cellulose acetate (powdered form) 15 35Carbon tetrachloride (100% dry) 29 Dibromdichlorethane 30 Bromoform 11In the mixing of the above chemical ingredients, I first place the 15%of tetrachlorethylene and the 15% cellulose acetate in an agitatingvessel and effect a thorough mixing of these ele- 5 ments until a liquidmixture is obtained. I have found that by using an agitator for themixing of these elements which consists of a rotating cylinder, and aseries of rotating baffle plates within the cylinder, the cylinder andbafile plates rotat- 50 ing in opposite directions, that an approximatetime period of twenty-four hours is required to thoroughly mix thetetrachlorethylene and cellulose acetate. The tetrachlorethylene servesas a solvent for reducing the cellulose acetate to a 55 liquid state.

The next step in the process of mixing the several ingredients, is toadd the 29% of carbon tetrachloride to the liquid mixture of celluloseacetate and tetrachlorethylene. This is performed by pouring the carbontetrachloride into the previously mixed elements and these combinedelements are agitated until thoroughly mixed. I have found that the mostefficient results have been obtained after these three elements havebeen agitated for approximately twenty-four hours in an agitator similarto the type above described. It is most efficient to employ.carbon-tetrachloride which is 100% dry, that is, free of any moisture.The fire extinguishing qualities of the vapors of carbontetrachloride iswell known in the art, but when used alone, or in a large percentage ina mixture, the same has been found highly toxic in use. When used in theproportion herein set forth, and in conjunction with the other elements,I am able to utilize the fire extinguishing qualities of this elementwithout the objectionable toxic efiect.

Dibrom'dichlorethane is known to be highly volatile and the properpercentage thereof is next added to the mixture of tetrachlorethylene,cellulose acetate, and carbon-tetrachloride. This mixture is also placedin an agitator and thoroughly agitated for a period of about eighthours, at which time the several elements are thoroughly mixed. However,for a precautionary measure, this mixture is strained by passing thesame through a chamois bag or other like strainer to remove any trace ofsolids which might be present therein.

To the strained mixture of elements, I add the 11% of bromoform. Thislast added element is also highly volatile and acts in the capacity ofan anti-freeze for the fire extinguishing liquid. The bromoform whenvaporized, is much heavier than the vapors of the carbontetrachloride,and coacts therewith in providing a vapor blanket for smothering theflames of burning material.

When used for fire extinguishing purposes, the herein described chemicalliquid is stored in the extinguisher apparatus or system for use whenneeded for the extinguishing of a fire. When sprayed or squirted upon afire, the heat or temperature of the burning material vaporizes theliquid which action lowers the temperature of the burning material dueto the displacement of air by the vapors which stop combustion. Thevapors from the chemical mixture being heavier than air, the same form aprotecting wall about the burning material and prevent air from reachingthe same, thus smothering the fire.

In the mixing of the several chemical elements, the cellulose acetatehas been liquefied by its mixture with the tetrachlorethylene, but whenthe chemical liquid is subjected to the heat of a fire, the celluloseacetate forms and deposits a film upon the burning materials, retardingthe flash-back of the fire and stifles combustion.

The use of the chemical liquid herein described when combating fire,results in an increase of vapor over carbon-tetrachloride generally usedas a fire fighting chemical, and also lowers the toxic efiect thereover.Further, the weight by volume of my fire extinguishing liquid is lessthan that of carbon-tetrachloride which makes it more practical forhandling in portable and hand type extinguishers.

Through experiments with this fire extinguishing liquid, I have foundthat it is very effective in the fighting of Class A as Well as Class3-2 and Class C2 fires as classified by the Bureau of Fire Underwriters.

While I have specifically mentioned certain proportions of the severalelements which make up my fire extinguishing liquid, the same may beslightly varied without unnoticeable effects and I do not wish to berestricted thereto. Also, other elements having similar characteristicswhich may be deemed equivalents may be substituted for those set forthwithout departing from the spirit of the invention.

Having thus described the invention, what I claim as new and desire tosecure by Letters Patent of the United States, is:

1. A fire extinguishing liquid including a highly volatilenon-combustible liquid substance, and cellulose acetate mixed with saidnon-combustible liquid, the cellulose acetate being substantially 15% ofthe total mass.

2. A fire extinguishing liquid including a highly volatilenon-combustible liquid substance, cellulose acetate mixed with saidnon-combustible liquid, and an anti-freeze agent combined therewith,said cellulose acetate and anti-freeze agent combined being less thanone-half of the total mass.

3. A fire extinguishing liquid comprising tetrachlorethylene, celluloseacetate, carbon-tetrachloride, and dibromdichlorethane, mixed insubstantially the proportions described, the amount ofcarbon-tetrachloride being less than 50% of the total mass.

4. A fire extinguishing liquid comprising tetrachlorethylene, celluloseacetate, carbon-tetrachloride, dibromdichlorethane, and bromoform, mixedin substantially the proportions described, the amount ofcarbon-tetrachloride being less than 30% of the total mass.

5. A fire extinguishing liquid comprising a highly volatilenon-combustible solution having therein a relatively small amount ofcarbon tetrachloride in proportion to the total mass, and a liquefiedcellulose acetate in amount equal to substantially 15% of the total massmixed with said solution.

6. A fire extinguishing liquid comprising a highly volatilenon-combustible solution having therein a relatively small amount ofcarbon tetrachloride in proportion to the total mass, at liquefiedcellulose acetate in amount equal to substantially 15% of the total massmixed with said solution, and a volatile anti-freeze agent addedthereto.

'7. A fire extinguishing liquid comprising the following elements insubstantially the proportions set forth:

Per cent Tetrachlorethylene 15 Cellulose acetate 15 Carbon tetrachloride29 Dibromdichlorethane 30 Bromoform 11 JAY LAWRENCE SEAT.

